Malicious PDF — malware analysis report

Static analysis result for SHA-256 4cf1a151fb6eae11…

MALICIOUS

PDF

75.3 KB Created: 2021-08-22 06:22:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 88beaeaf4981db3a4e306c442f57f2ce SHA-1: 13d3e0002b3a49c7a8287f07b3163ae6a13ca3af SHA-256: 4cf1a151fb6eae11b441815a5ac952d2f310b5fc080603677d20efd5dee8709d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites utilizing the 'super-forms' plugin for file uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The presence of link farms on disposable hosting and compromised CMS upload directories suggests a tactic to obscure the ultimate destination and evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://allytemp.ru/uplcv?utm_term=estatica+para+ingenieros+y+arquitectos+pdf
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/5e5dbc100d9ede8b3df75aaff9cd89a7/42641487145.pdf
    • https://plagij.at/ckfinder/userfiles/files/luxok.pdf
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/jumubowutisuvan.pdf
    • http://matstravel.ru/userfiles/file/64341763922.pdf
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/mpas2q6gsqphuuei6ve0ei777o/jupopuzopuvatubozidubas.pdf
    • https://www.agcontraincendios.es//ckfinder/userfiles/files/kebepijul.pdf
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/21cd2e64cd759d0a752e4a714f327d61/fipugadazesubax.pdf
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9c9ea88bb---sijas.pdf
    • https://karinbentum.nl/uploads/file/48698832432.pdf
    • http://gyogytornasziget.hu/uploads/files/45544618824.pdf
    • https://sunarchegypt.com/userfiles/file/dekulimewufapevitaxegol.pdf
    • https://gkia.org/kingkong/userfiles/files/87765647404.pdf
    • https://monamifrance.com/FileData/ckfinder/files/20210702_8D74A2D5B4FB753E.pdf
    • http://www.deco-interieure.com/userfiles/file/gamakususiwubemome.pdf
    • https://geniodelweb.com/file/sikixabumajogekupakum.pdf
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/5ea52b79202e8264e5a8f5975aa3bbb2/2009377254.pdf
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/d0d80634907459560eceb5cc3170323c/28674802485.pdf
    • https://stagerightstaging.com/wp-content/plugins/super-forms/uploads/php/files/acdd2855646f47aebf666fb851cfb8b4/vemuduziwegujupe.pdf
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/160805939bec25---ribevetulefabuf.pdf
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160816df1cdda4---65968961171.pdf
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/48906ef16405b6e264f3f7b158219df0/55932934494.pdf
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160a9e10abf02f---75849524736.pdf
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160b9e9430730d---jefipikumejinujeronotux.pdf
    • https://cnn-logistics.com/asset/files/zumepekarafigarotizas.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000baa9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBAA9 16792 bytes
font_01_sfnt_off0000d2c0.bin
2de5688113209869b25eb04033157d7ceefbb117782988eb324e0edfff522d1c
pdf-font-stream PDF embedded font (sfnt) at offset 0xD2C0 11092 bytes
font_02_sfnt_off0000ec46.bin
32e69848b9ef2290dd6a896d1ded183d0a1c20aae34b03e83e435d1051e34727
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC46 19772 bytes